Kai K, Takagi K, Iyama K, Kitaoka M, Yoshioka H, Mizuta H, Usuku G
Department of Orthopaedic Surgery, Kumamoto University Medical School, Japan.
Clin Orthop Relat Res. 1992 Jun(279):292-8.
The purpose of this study was to investigate the relationship between the appearance of basal lamina components (Type IV collagen and laminin) and the development of cartilage canals. In the distal femoral epiphyses from developing rats, the distribution of basal lamina components in the cartilage canal was examined immunohistochemically. The formation of cartilage canals from the perichondrium was first observed on the fifth day after birth. By Day 8, a few cartilage canals penetrated the epiphyseal cartilage and considerably increased in size and length. By light microscopic immunohistochemistry, reticular structures stained with anti-Type IV collagen and antilaminin antibodies were observed in the cartilage canals. In the early development of cartilage canals, however, immunostaining by anti-Type IV collagen antibodies was weaker than that by antilaminin antibodies. In eight-day-old rats, the laminin-positive reticular structures were more densely colored and more widely distributed in the canal than the Type IV collagen-positive ones. Type IV collagen was found around the endothelial cells of the developing capillaries by electron microscopic immunohistochemistry. Laminin was observed in the cytoplasm of the mesenchymal fibroblastic cells and their pericellular matrix as well as in the capillary basal lamina. These immunohistochemical electron microscopic observations can explain the differences that are observed in Type IV collagen and laminin immunostaining patterns as cartilage canals develop. Laminin synthesized by the mesenchymal fibroblastic cells may promote the migration and the outgrowth of endothelial cells in the formation of cartilage canals.
本研究的目的是探讨基底层成分（IV型胶原蛋白和层粘连蛋白）的出现与软骨管发育之间的关系。在发育中大鼠的股骨远端骨骺，采用免疫组织化学方法检测软骨管中基底层成分的分布。出生后第5天首次观察到软骨膜形成软骨管。到第8天，一些软骨管穿透骨骺软骨，其大小和长度显著增加。通过光学显微镜免疫组织化学观察，在软骨管中观察到用抗IV型胶原蛋白和抗层粘连蛋白抗体染色的网状结构。然而，在软骨管的早期发育中，抗IV型胶原蛋白抗体的免疫染色比抗层粘连蛋白抗体的弱。在8日龄大鼠中，层粘连蛋白阳性的网状结构比IV型胶原蛋白阳性的结构在管内染色更密集、分布更广泛。通过电子显微镜免疫组织化学发现IV型胶原蛋白存在于发育中毛细血管的内皮细胞周围。层粘连蛋白在间充质成纤维细胞的细胞质及其细胞周围基质以及毛细血管基底层中均有观察到。这些免疫组织化学电子显微镜观察结果可以解释在软骨管发育过程中IV型胶原蛋白和层粘连蛋白免疫染色模式中观察到的差异。间充质成纤维细胞合成的层粘连蛋白可能在软骨管形成过程中促进内皮细胞的迁移和生长。
